Note 12 - Disaggregated Net Revenues - Net Revenue, Classified by Geography (Details) - USD ($)
12 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Net revenues $ 3,206,594 $ 3,090,631
Chemical [Member]    
Net revenues 1,319,578 1,244,361
Electronics [Member]    
Net revenues 1,405,594 1,328,719
Engineering [Member]    
Net revenues 481,422 517,551
UNITED STATES    
Net revenues 2,920,410 2,823,691
UNITED STATES | Chemical [Member]    
Net revenues 1,033,394 977,422
UNITED STATES | Electronics [Member]    
Net revenues 1,405,594 1,328,719
UNITED STATES | Engineering [Member]    
Net revenues 481,422 517,550
Non-US [Member]    
Net revenues 286,184 266,940
Non-US [Member] | Chemical [Member]    
Net revenues 286,184 266,940
Non-US [Member] | Electronics [Member]    
Net revenues 0 0
Non-US [Member] | Engineering [Member]    
Net revenues $ 0 $ 0